[125I]iodomelatonin binding sites in spleens of birds and mammals

The specific binding of [125I]iodomelatonin to duck spleen membrane preparations was studied in detail. These binding sites were stable, saturable, reversible and of high affinity. Scatchard analysis of the binding revealed a equilibrium binding constant (Kd) of 73.1 +/- 5.4 pM and a total number of binding sites (Bmax) of 3.64 +/- 1.38 fmol/mg protein. Studies on the relative binding capacities of [125I]iodomelatonin to the spleen in different species showed the following order: duck greater than chicken greater than guinea pig greater than pigeon greater than mouse. No binding site was detected in the rat spleen. The presence of [125I]iodomelatonin binding sites in the spleen of birds and mammals suggested a direct action of pineal melatonin on the immune system.

Regulation of testicular P-450 cholesterol side-chain cleavage and P-450 C17-20 lyase/C17 hydroxylase enzymes in the neonatal and adult rat

Adult Leydig cells respond to LH or hCG with an initial stimulation of testosterone secretion followed by LH receptor down-regulation and blockade of androgen biosynthesis. In contrast, fetal Leydig cells respond with increased LH receptor number and enhanced steroidogenesis. In this study, the molecular mechanisms of high-dose hCG treatment on steroidogenesis in adult and neonatal testes (containing predominantly the fetal generation of Leydig cells) were examined using two recombinant DNA clones specific for enzymes of the rat steroidogenic pathway (P-450 cholesterol side-chain cleavage enzyme, P-450scc and P-450 17 alpha-hydroxylase/C17-20 lyase, P-450c17). We treated adult (60 days of age) and neonatal (2 days of age) rats with a single high dose of hCG (600 IU/kg), sc. The high dose of hCG caused neonatal testicular P450scc and P450c17 mRNA levels to increase, and stimulated adult testicular P450scc mRNA levels, but caused a decrease in adult P450c17 mRNA levels. These studies suggest that high doses of hCG regulate testosterone production differently in adult and fetal Leydig cells at a pretranslational level of the P450c17 enzyme, while mRNA for P450scc is stimulated in both the adult and fetal Leydig cell.

Regulation of glycan processing by Golgi enzymes from red kidney bean (Phaseolus vulgaris) seedlings

The effect of a protein matrix on the processing of glycoprotein glycans by Golgi enzymes from plant seedlings has been determined with an artificial glycoprotein system, comparing the processing rates of glycan-(biotinyl)Asn (or glycan-(biotinamidohexanoyl)Asn) substrates either free or bound to avidin. An analysis of the pooled glycoproteins from the seedlings suggested that the most common glycan structure is a complex one (GlcNAc-Man3GlycNAc2-protein), and consistent with this processing end-product, mannosidases I and II and GlcNAc transferases I and II were all found to be present in the seedling Golgi membrane preparations. The effect of the avidin matrix either in a proximal (biotinyl substrates) or distal (N-(biotinamido)hexonoyl substrates) association with the appropriate glycan substrate for these four enzymes was assessed from the direct comparison of the apparent first-order rate constants for the free and avidin-bound substrate-product conversions. All four plant enzymes were inhibited by the association of the glycan substrates with avidin, but the inhibition was much less pronounced than that observed with the corresponding enzymes from rat liver and hen oviduct. The rate effect shows a progression from 3- to 10-fold rate decreases in the proximal complexes and 2- to 3-fold in the distal complexes in going from the first (mannosidase I) to the fourth (GlcNAc transferase II) enzyme; with the mammalian and avian enzymes the largest effects were for the first ones and much larger absolute rate effects were observed. The results suggest that the nature of the processing enzymes in terms of this response to the avidin glycan substrates may differ in different organisms.

Expression of chimeric human transferrin genes in vitro

Transferrin (TF), a major plasma protein, binds and transports ferric iron. Evidence exists for unique roles for TF in brain in oligodendrocyte differentiation, myelination and neuronal development. In this study, 5' flanking regions of the TF gene important in regulating gene expression were identified by transfected cell studies and a comparison of 5' flanking sequences of the human TF and TF receptor genes. Human glioma cell lines HTB-16 and HTB-17 were shown to synthesize TF identical in size and immunological reaction to TF synthesized by liver. The expression of a series of human chimeric TF genes in glioma cells was compared with hepatoma and HeLa cells. A difference in transient expression was observed in hepatoma and glioma cells transfected with TF chimeric genes containing 3.9 kb of the 5' region; hepatoma cells demonstrated significantly more expression than did glioma cells, suggesting that a DNA region present in the 3.9-kb construct is important either in liver-specific expression or in repression of brain expression, or in both. Smaller constructs containing less than or equal to 0.622 kb of the 5' regulatory region of the TF gene failed to demonstrate cell-specific expression; they were expressed in HeLa cells, a line that does not synthesize TF. High levels of expression of 0.15-kb TF constructs were also observed in hepatoma and glioma cell lines, but not in transgenic mice. Possible explanations of differences observed in expression of shorter TF constructs in vitro and in vivo are discussed.

Interactions between N-methyl-D-aspartate and CGS 19755 administered intramuscularly and intracerebroventricularly in pigeons

Behavioral effects of N-methyl-D-aspartate (NMDA) and the competitive NMDA antagonist cis-4-phosphonomethyl-2-piperidine-carboxylic acid (CGS 19755) were studied in pigeons. NMDA decreased responding under a fixed-ratio schedule of food presentation and was 8000 times more potent administered intracerebroventricularly (i.c.v.) as compared to intramuscularly (i.m.). CGS 19755 was 870 times more potent in producing catalepsy when administered i.c.v.; however, the duration of catalepsy was similar by the two routes of administration. Administered i.m. CGS 19755 decreased response rates only at doses that also produced catalepsy; administered i.c.v. some doses of CGS 19755 decreased responding without producing other behavioral effects. Rate-decreasing effects of i.m. NMDA were attenuated by i.m. CGS 19755; however, when CGS 19755 was administered i.c.v., there was little or no antagonism of NMDA. Rate-decreasing effects of i.c.v. NMDA were not attenuated by i.m. or i.c.v. CGS 19755 up to doses that produced catalepsy or eliminated responding. The large difference in potency between i.m. and i.c.v. administration for NMDA and for CGS 19755, as well as the slower onset of catalepsy when CGS 19755 was administered i.m., suggests these compounds do not readily cross the blood-brain barrier when administered parenterally. The inability of CGS 19755 to attenuate the rate-decreasing effects of NMDA when CGS 19755 or NMDA was administered i.c.v. suggests NMDA might decrease responding by different mechanisms when administered i.m. or i.c.v. in pigeons. Together these results indicate antagonism of NMDA in this study, and perhaps in other studies, when both NMDA and CGS 19755 were administered parenterally, might result from a peripherally mediated interaction. Moreover, this agonist-antagonist interaction is not a simple, competitive antagonism.

[Inhibition of growth and metastases of lung carcinoma in C57BL/6 mice by Corynebacterium parvum and its antitumor mechanism]

Cocrynebacterium parvum (CP) was injected around the tumor and tumor cells were inoculated subcutaneously with activated peritoneal macrophages. The effects on the growth and metastases of Lewis lung carcinoma in C57BL/6 mice were observed. Experimental results indicated that CP had significant inhibitory effect on the tumor growth and lung metastases. The cytotoxic effects of activated peritoneal macrophages in mice on target tumor cells (L5178Y) in vitro were studied with the technique of 3H-TdR assay. The proliferation of tumor cells was markedly inhibited by the activated peritoneal macrophages of CP. Experiments showed that the antitumor mechanism of CP was the mediation via activated cytotoxic macrophages. These results indicated that CP is an effective immunostimulant. These findings will provide a scientific basis for the clinical treatment of the primary and metastatic lung carcinoma.

CT-guided transcutaneous fine-needle aspiration biopsy. A report of 350 cases

CT-guided transcutaneous fine-needle aspiration biopsies were done in 350 patients. They involved the abdomen in 226 patients (liver 75, pancreatic and abdominal masses 51, kidney 96, adrenal gland 3, spleen 1), thorax 90, musculoskeletal system 32, and brain 2. The accuracy varied with different locations. The accuracy of liver biopsy was 94%, kidney 95.8%, pancreatic and abdominal masses 88.2%, thorax 90%, and musculoskeletal system 96.5%. The occurrence rate of complications was 2.3%. Pneumothorax occurred in 7 patients having thorax biopsy, and gastric perforation in one patient after abdominal biopsy. The proper selection of fine needles, the method and technique, the influential elements of the accuracy, and the application of CT-guided aspiration biopsy were detailed in this paper.

Tumor necrosis factor and interleukin-1 stimulate testosterone secretion in adult male rat Leydig cells in vitro

The actions of two cytokines, tumor necrosis factor (TNF) and interleukin-1 (IL-1), on testosterone production by dispersed adult testis cells and purified Leydig cells in culture were studied. In one set of experiments, testis cells from adult (90-day-old) rats were enzymatically dispersed. In another set of experiments, the dispersed testis cells were placed on a Percoll density gradient and were centrifuged to yield purified (greater than 85%) Leydig cells. Both whole testis cells and purified Leydig cells were cultured in the presence of varying doses of TNF or IL-1 with or without maximally stimulating doses of human chorionic gonadotropin (hCG). Both TNF and IL-1 stimulated basal secretion of testosterone in whole testis cells, as well as purified Leydig cells. Additionally, both TNF and IL-1 augmented maximally hCG stimulated testosterone secretion. Both cytokines stimulated testosterone secretion by dispersed testis cells as early as 4 hours, and the effect continued for up to 72 hours. The cytokines slightly, but significantly, stimulated testosterone production in purified Leydig cells after 24 hours, and continued for up to 72 hours. We have concluded from this data that TNF and IL-1 stimulate the testosterone secretion by adult rat Leydig cells. While this effect might be mediated through the action of the cytokines on testicular macrophages, there might also be a direct effect on the Leydig cell since augmentation of secretion occurred in purified Leydig cells, as well as whole testis cells. Therefore, TNF and IL-1 may serve as local regulators of Leydig cell function.

Growth of the penaeid shrimp virus infectious hypodermal and hematopoietic necrosis virus in a fish cell line

An established fish cell line, epithelioma papillosum cyprini (EPC), originating from the carp (Cyprinus carpio) was found to be susceptible to the penaeid shrimp virus, infectious hypodermal and hematopoietic necrosis virus (IHHNV). This economically important pathogen of penaeid shrimp raised in mariculture has been previously limited to growth only in young post-larval shrimps. This is, to our knowledge, the first reported successful growth of the penaeid virus in a fish cell line; it promises to provide a sensitive and convenient cell culture system for the primary isolation and detection of IHHNV which will aid immensely the production of IHHNV-free penaeid shrimp stocks for mariculture. Of added significance is the replication of a crustacean virus in a fish cell line which has never before been reported. The use of this sensitive cell line will also greatly facilitate the characterization of the IHHN virus and other crustacean viruses.

Evaluation of N-4-(hydroxycarbophenyl) retinamide as a cancer prevention agent and as a cancer chemotherapeutic agent

In this review, a retinoid analogue (N-4-hydroxycarbophenyl) retinamide (R11) has been evaluated for its pharmacological and clinical properties. R11 has been studied both as a cancer prevention agent, as well as, a cancer chemotherapeutic agent. R11 alone and in combination with other agents can be used for the treatment of cervical dysplasia or leukemia. This review will examine novel strategies and mechanisms of action for retinoids in the treatment and prevention of cancer.

Differential oncogene amplification in tumor cells from a patient treated with cisplatin and 5-fluorouracil

Peritoneal cells were derived from a patient (PK) with adenocarcinoma of the colon during the course of cisplatin/5-fluorouracil (5-FUra) treatment. Resistance to cisplatin and 5-FUra, characterized by a lack of response to chemotherapy and continued growth of the tumor, was concomitantly associated with a 2-4-fold increase in DNA copy number for dTMP synthase and dihydrofolate reductase. There was a corresponding amplification in DNA copy number of the c-myc (2X), H-ras (4X), and c-fos (15X) oncogenes. Cytogenetic studies revealed an iso (13q) chromosome, but failed to show any double minutes or homogeneously staining regions. In addition, drug-resistant tumor cells from PK and another patient (HG) displayed enhanced expression of dTMP synthase, c-fos and DNA polymerase beta when compared to normal colon tissue and the HCT8 human colon carcinoma cell line. These results suggest that elevated oncogene DNA and gene expression may be involved in the development of cisplatin resistance.

Expression of chimeric human transferrin genes in transfected human tumor cell lines

The iron-binding plasma protein transferrin (TF) is essential for supplying iron to cells and the prevention of iron toxicity. Our laboratory has cloned and characterized the human TF gene. Comparison of promoter regions of TF genes from human, chicken, and mouse reveals a strong nucleotide sequence conservation. This study demonstrates that 5' flanking regions of the TF gene are sufficient for directing expression of a heterologous gene in transgenic mice and transfected cells. For cell-specific expression, more than 150 base pairs appear to be required.

Isolation, purification and characterization of infectious hypodermal and hematopoietic necrosis virus (IHHNV) from penaeidshrimp

A protocol was developed for the isolation and purification of the infectious hypodermal and hematopoietic necrosis virus (IHHNV) of penaeid shrimps. Cesium chloride-banded virus obtained from three sources of infected shrimps was found to have a buoyant density of 1.33 g/cm3. Also, electron microscopical studies employing negative stain revealed isometric particles having a size of 19 +/- 1 nm. Colorimetric analysis of its nucleic acid type indicated that these particles contain only RNA.

[CT investigation of renal cystic masses]

This report presented 61 cases of renal cystic masses including renal parenchymal cyst 57 cases; parapelvic cyst 2; cystic hypernephroma 1 and calyceal diverticulum 1 case. All were confirmed by CT guided puncture and aspiration. The CT features of various renal cysts. complications and some special manifestations as well as differential diagnosis were discussed. Pertinent analysis of the CT features are necessary for correct diagnosis and proper management.

Effects of long terminal repeat mutations on human immunodeficiency virus type 1 replication

The effects of deletions within three functional regions of the long terminal repeat of human immunodeficiency virus type 1 upon the ability of the long terminal repeat to direct production of the chloramphenicol acetyltransferase gene product and upon the ability of viruses that carry the mutations to replicate in human cell lines was investigated. The results show that the enhancer and TATAA sequences were required for efficient virus replication. Deletion of the negative regulatory element (NRE) yielded a virus that replicated more rapidly than did an otherwise isogeneic NRE-positive virus. The suppressive effect of the NRE did not depend upon the negative regulatory gene (nef), as both NRE-positive and NRE-negative viruses were defective for nef. We conclude that factors specified by the cell interact with the NRE sequences to retard human immunodeficiency virus type 1 replication.

The therapeutic efficacy of the choleretic mixture against the infantile hepatitis syndrome

Observation was made on a control study of the therapeutic efficacy of the choleretic mixture in treating 35 cases of infantile hepatitis syndrome in comparison with that of the choleretic decoction. The ages, duration of the disease, severity of icterus and serum bilirubin level in both groups were comparable. The results showed that there was no significant difference in therapeutic efficacy between the two groups, however, the resolving time of skin icterus was faster in the choleretic mixture group than in the choleretic decoction group. The choleretic mixture was convenient, easy to store, and acceptable to infants for its small dosage, and no side effects, therefore, a desirable drug against infantile hepatitis syndrome.

The vascular microanatomy of skin territory of posterior forearm and its clinical application

We have undertaken a microanatomical study of a new donor site--the posterior forearm territory--on 43 cadaver arms. Two axial arteries were found, and both the fasciocutaneous flap and the fascial flap could be elevated with the two arteries on the posterior forearm. The posterior forearm flap was transferred to the hand to repair deformities of the wrist, the first web space, the dorsal hand, and the metacarpophalangeal joints in eight cases. The result was very satisfactory. The posterior forearm flap is near the hand, easy to perform, and reliable. It is a one-stage operation and does not sacrifice a main artery. In this article we demonstrate our own ideas about flap extension, which is valuable for clinical application.